Rumen bypass calcium salts of c18:1 and c18:2 fatty acids

ABSTRACT

Free-flowing unsaturated fatty acid calcium salts containing from about 0.1 to about 1.5 equivalents of calcium hydroxide relative to the fatty acid content, with the fatty acid content consisting essentially of  
     (a) from about 40 to about 95% percent by weight of unsaturated C:16-C:22 fatty acids; (b) from about 5 to about 60% by weight of saturated C:14-C:22 fatty acids; and (c) no more than about 6% by weight of moisture, insolubles and unsaponifiables; with no more than about 20% by weight being in for form of glycerides;  
     wherein from about 40 to about 65% by weight of the total product weight consists of trans-C18:1 and C18:2 fatty acids; provided that when less than 0.75 equivalents of calcium hydroxide is present, the fatty acid content is at least 25% by weight saturated fatty acids.

BACKGROUND OF THE INVENTION

[0001] The present invention relates to calcium salts of unsaturatedfatty acids that are of particular interest as nutritional supplements.

[0002] Unsaturated fatty acids undergo hydrogenation to saturated fattyacids by microbial action in the rumen and must be fed to ruminants in aprotected form. U.S. Pat. No. 5,143,737 discloses the encapsulation ofunsaturated fatty acids with non-toxic organic materials to protect theunsaturated fatty acids from microbial action in the rumen. The mostfamiliar form in which fatty acids in general are protected frommicrobial action in the rumen are the fatty acid calcium salts disclosedby U.S. Pat. Nos. 4,642,317; 4,826,694; 4,853,233 and 4,909,138. Thisform of fatty acid protection is widely accepted in the dairy and beefcattle industries.

[0003] Unsaturated fatty acids, however, do not readily react to formcalcium salts using the processes disclosed by the above-listed patents.Instead of forming free-flowing granules, a mass develops that hardensinto a tough material that resists grinding into the fine particlesrequired for consumption by cattle. The resulting material also lacksstorage stability. The product tends to auto-oxidize through anexothermic reaction that leads to a congealing of the product mass hornits free flowing granular state to a hard amorphous state, suggestingthat significant quantities of unreacted starting materials are presentin the final product.

[0004] To be commercially viable, rumen-protected unsaturated fatty acidcattle feed supplements must be in a form acceptable to the cattleindustry. Therefore, a need exists for unsaturated fatty acid calciumsalts that are storage stable and easily formed into particles smallenough for cattle to consume that also confer a nutritional benefit tothe cattle.

SUMMARY OF THE INVENTION

[0005] This need is met by the present invention. It has been discoveredthat storage stable calcium salts of unsaturated fatty acids can beproduced in fine particle form either by using elevated levels ofcalcium oxide, or by reducing the amount of unsaturated fatty acids inthe fatty acid feedstock. The preparation of such fatty acids isdisclosed in co-pending and commonly-owned U.S. Pat. No. 6,559,334, thedisclosure of which is incorporated herein by reference.

[0006] It has further been discovered that cows fed a rumen-protectedsource of trans-C18:1 fatty acids will have decreased concentrations ofmilk fat, hepatic triacylglycerol, and lower incidence of sub-clinicalketosis during early postpartum, and that feeding a rumen-protectedsource of linoleic (C18:2) fatty acids during the transition period willincrease synthesis of PGF_(2α). The linoleic fatty acids are will thushasten uterine involution and reduce the incidence of clinical andsubclinical uterine inflammation; which translates to increasedfertility. The present invention combines both sources of fatty acidsinto one calcium salt feed supplement product that when fed to alactating cow will achieve a better transition phase.

[0007] According to one aspect of the present invention, a free-flowingunsaturated fatty acid calcium salt product is provided containing fromabout 0.1 to about 1.5 equivalents of calcium hydroxide relative to thefatty acid content, with the fatty acid content consisting essentiallyof

[0008] (a) from about 40 to about 95% percent by weight of unsaturatedC:16-C:22 fatty acids; (b) from about 5 to about 60% by weight ofsaturated C:14-C:22 fatty acids; and (c) no more than about 6% by weightof moisture, insolubles and unsaponifiables; and with no more than about20% by weight being in the form of glycerides;

[0009] wherein from about 40 to about 65% by weight of the total productweight consists of trans-C18:1 and C18:2 fatty acids; provided that whenless than 0.75 equivalents of calcium hydroxide is present, the fattyacid content is least 25% by weight of saturated fatty acids.

[0010] In preferred products according to the present invention theratio of trans-C18:1 and C18:2 is between about 60 and about 80% byweight of trans-C18:1 to between about 20 and about 40% by weight ofC18:2.

[0011] The above and other features and advantages of the presentinvention will become clear from the following description of thepreferred embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] The present invention employs a process by which highlyunsaturated fatty acid feedstocks may be converted to free-flowingpowder or granular fatty acid calcium salt rumen bypass feedsupplements. The use of highly unsaturated fatty acid feedstocksrepresents a significant departure from conventional processes for themanufacture of fatty acid calcium salt feed supplements.

[0013] The process is employed as either a batch or a continuousprocess. In a typical process fatty acid feedstocks are added to aproduction vessel. The mixing should be accomplished in a kettledesigned so that intensive and intimate contacting occurs between thecalcium oxide and fat admixture so that a homogeneous dispersion of thecalcium oxide particles results. Kettles may be either vertical orhorizontal in configuration, and there is no need for jacketing for thepurpose of heat input since the unit is operated adiabatically (noexternal heat input or output). The types of internal mixing elementsspan a wide gap but would include those with propeller, turbine, plowswith chopper blades, or preferably ‘Cowles-type’ mixing blades asexamples, but others may apply. These same devices are also be suitablefor dispersing and homogenizing the water fraction into the fatadmixture and calcium oxide.

[0014] Unsaturated fatty acid feedstocks are employed containing fromabout 40 to about 95% by weight of unsaturated C:16-C:22 fatty acids.The feedstocks should contain no more than about 6% by weight ofmoisture, insolubles and unsaponifiables and no more than about 20% byweight of the fatty acids should be in the form of glyceride. Ingeneral, unsaturated fatty acids having from 16-22 carbon atoms and fromone to six double bonds are suitable for use with the present invention.

[0015] Essentially, any source of unsaturated fatty acids may beemployed, inclusive of fatty acid sources of animal, vegetable or fishorigin. This includes distillates and soap stocks of lard, tallow,vegetable oils such as canola oil, sunflower oil, safflower oil,rapeseed oil, soybean oil, olive oil, corn oil, and the like, andbyproducts thereof, as well as fish oils and byproducts thereofPre-treatment processes may be needed to reduce moisture, insolubles,unsaponifiables, and glycerides below about 10% by weight. The level ofglycerides, which include monoglycerides, diglycerides andtriglycerides, may be reduced by hydrolysis or saponification.

[0016] The unsaturated fatty acid feedstocks are selected on the basisof trans-C18:1 and C18:2 content. Fatty acid feedstocks high intrans-C18:1 content (about 50 weight percent and higher, and typicallybetween about 50 and about 75 weight percent) are obtained from soybeanoil. Fatty acid feedstocks high in C18:2 content (about 50 weightpercent and higher, and typically between about 50 and about 75 weightpercent) are obtained from safflower oil, although any appropriatesource of either or both fatty acids may be used with the invention.

[0017] When the amount of calcium oxide falls below 1.75 equivalentsrelative to the amount of fatty acid, the amount of saturated fattyacids in the feedstock must be at a level of 25% by weight or greater.Feedstocks having less than 25% by weight of saturated fatty acids mustbe blended with another fatty acid feedstock having greater than 25% byweight of saturated fatty acids in an amount effective to produce atleast 25% by weight of saturated fatty acids in the resulting admixture.A preferred source of saturated fatty acids is palm fatty aciddistillate (PFAD). The fatty acid feedstock with higher levels ofsaturated fatty acids can be present in a blend at a level up to about 5and about 60% by weight, and preferably between about 5 and about 30% byweight. Such blends can be reacted with greater than 1.75 equivalents ofcalcium oxide, although such calcium oxide levels are not necessary toproduce a commercially acceptable product when saturated fatty acidlevels exceed 25% by weight.

[0018] Saturated fatty acids have higher melting points than unsaturatedfatty acids. Accordingly, it may be necessary to heat the unsaturatedfatty acid feedstock to form a uniform, liquid admixture with the secondfatty acid feedstock having a combined saturated fatty acid content of25% by weight or greater. A temperature up to about 80° C. is suitable,with a temperature between about 50 and about 60° C. being preferred.

[0019] Calcium oxide is added to the fatty acid feedstock in the rangeof from about 1.0 to about 2.5 equivalents relative to the fatty acidfeedstock. A calcium oxide level above about 1.4 equivalents ispreferred, with about 1.75 equivalents being more preferred, so thathighly unsaturated fatty acid feedstocks may be employed. A calciumoxide level between about 2.0 and 2.3 equivalents is most preferred.

[0020] Water is then added to hydrate the calcium oxide to its hydroxideform, creating a large amount of exothermic heat. The heat that isevolved is sufficient for the fatty acid neutralization reaction toproceed to completion, so that it is not necessary to supply heat to thereaction mixture from external sources from this point forward. Betweenabout two and about five equivalents of water relative to the calciumoxide is added to the reaction mixture, with between about 2.5 and about3.5 equivalents being preferred. Calcium hydroxide may be substitutedfor equivalent quantities of calcium oxide and water.

[0021] The excess water is converted to steam by the exothermic heatgenerated, which boils off rapidly. The reaction can be performed underatmospheric pressure, or under vacuum to draw off the steam.

[0022] The amount of time required for the reaction is typically betweenabout 5 and about 60 minutes, and more typically between about 6 andabout 10 minutes. The reaction is easily identified by thetransformation of the admixture into a solid granular mass Upon furtheragitation, the mass further transforms into a free-flowing granularmaterial, which, upon transfer from the reaction vessel, can easily beprocessed into free-flowing particles.

[0023] Products according to the present invention will contain fromabout 40 to about 65% by weight of trans-C18:1 and C18:2 fatty acids.Particularly preferred products have a total fatty acid content of about85 weight percent. The trans-C18:1 and C18:2 fatty acids are present ina ratio between about 60 and about 80 weight percent trans-C18:1 tobetween about 20 and about 40 weight percent C18:2, with a ratio ofbetween about 65 and about 75 weight percent trans-C18:1 to betweenabout 25 and about 35 weight percent C18:2 being more preferred. A 70:30weight ratio of trans-C18:1 to C18:2 is most preferred.

[0024] A biologically active material can be included as an optionalingredient in the invention process. By the term “biologically activematerial”, it is meant any substance capable of being administeredorally in a feed composition. Preferred biologically active materialsare susceptible to inactivation in the rumen bimicrobes and digestivejuices, and are thereby protected therefrom by incorporation into thefatty acid calcium salts of the present invention. The biologicallyactive material can be selected from a broad variety of nutrients andmedicaments, either as a single component or as a mixture of components,which are illustrated by the following list of active molecular species:

[0025] 1. Sugars and complex carbohydrates which include bothwater-soluble and water insoluble monosacchandes , disaccharides andpolysaccharides. Particularly preferred carbohydrates include canemolasses and sugar beet byproducts.

[0026] 2. Amino acid ingredients, either singly or in combination, whichinclude arginine, histidine, isoleucine, leucine, lysine, methionine,phenylalanine, threonine, tryptophan, valine, tyrosine ethyl HCl,alanine, aspartic acid, glutamic acid, sodium glutamate, potassiumglutamate, glycine, proline, serine, cystine ethyl HCl, and the like;and analogues and salts thereof.

[0027] 3. Vitamin ingredients, either singly or in combination,including thiamine HCi, riboflavin, pyridoxine HCl, niacin, inositol,choline chloride, calcium pantothenate, biotin, folic acid, ascorbicacid, Vitamin B,Z, p-aminobenzoic acid, Vitamin A acetate, Vitamin K,Vitamin B, Vitamin E, and the like.

[0028] 4. Trace element ingredients, either singly or in combination,including compounds of cobalt, copper, manganese, iron, zinc, tin,nickel, chromium, molybdenum, iodine, chlorine, silicon, vanadium,selenium, calcium, magnesium, sodium and potassium

[0029] 5. Protein ingredients obtained from sources such as dried bloodor meat meal, meat and bone meal, cottonseed meal, soybean meal,rapeseed meal, sunflower seed meal, canola meal, safflower meal,dehydrated alfalfa, corn gluten meal, soybean protein concentrate,potato protein, dried and sterilized animal and poultry manure, fishmeal, fish and poultry protein isolates, crab protein concentrate,hydrolyzed protein feather meal, poultry byproduct meal, liquid orpowdered egg, milk whey, egg albumen, casein, fish solubles, cell cream,brewer's residues, and the like.

[0030] 6. Medicament ingredients, either singly or in combination,including promazine hydrochloride, chloromedoniate acetate,chlorotetracycline, sulfamethazine, monensin, sodium monensin,poloxalme, oxytetracycline, BOVATEC, and the like.

[0031] 7. Antioxidants, including butylated hydroxyanisole, butylatedhydroxytoluene, tertiary butylhydroquinone, tocopherols, propyl gallateand ethoxyquin; and preservatives, including sodium sorbate, potassiumsorbate, sodium benzoate, propionic acid, ∝-hydroxybutenc acid, and thelike.

[0032] The biologically active material is present at a level up toabout 20% by weight relative to the fatty acid.

[0033] The unsaturated fatty acid calcium salt rumen bypass feedsupplements of the present invention may be conveniently fed to aruminant admixed with a conventional ruminant feed. The feeds aretypically vegetable materials edible by ruminants, such as legume hay,grass hay, corn silage, grass silage, legume silage, corn grain, oats,barley, distiller's grain, brewer's grain, soya bean meal and cottonseedmeal. There is no particular lower limit of the calcium salt to be addedto the ruminant feed, although in practice, amounts of the calcium saltbelow about 1% of the dry solids content of the feed are too small toprovide significant benefits.

[0034] The following non-limiting example illustrates certain aspects ofthe invention. All parts and percentages are by weight, and alltemperatures are in degrees Celsius.

EXAMPLE

[0035] 13.8 pounds of calcium oxide was added to a vertical mixer withCowles-type mixing blades containing 78.2 pounds of a mixture of soybeanoil (hydrogenated to provide a trans-C18:1 content of 60 weight percent)blended with safflower oil. The respective amounts of the two oils wereselected to provide 60 percent total product weight of trans-C18:1 andC18:2 in a 70:30 ratio of trans-C18:1 to C18:2. The oils had byconcentration 95% by weight free fatty acid. The total unsaturated fattyacid content was 90% by weight. Prior to adding the calcium oxide, theoil blend was heated to a temperature of 60° C. After the calcium oxidewas uniformly dispersed, 10.8 pounds of water was added, and thetemperature of the mixture rose to 120° C. Agitation continued until auniform, homogenous mixture was obtained, which was dumped from thevessel into a tray, in which the reaction went to completion and theproduct cooled. Milling of the finished product produced a free-flowinggranule that was not dusty having a total fat content of about 83% byweight.

[0036] The present invention thus provides a method by whichrumen-protected fatty acid calcium salts high in trans-C18:1 and C18:2content may be prepared in a form familiar to and accepted by the dairyand cattle industry for supplementation of cattle diets to improve cowfertility. The foregoing examples and description of the preferredembodiment should be taken as illustrating, rather than as limiting, thepresent invention as defined by the claims. As will be readilyappreciated, numerous variations and combinations of the features setforth above can be utilized without departing from the present inventionas set forth in the claims. Such variations are not regarded as adeparture from the spirit and scope of the invention, and all suchmodifications are intended to be included within the scope of thefollowing claims.

What is claimed is:
 1. A free-flowing unsaturated fatty acid calciumsalt comprising from about 0.1 to about 1.5 equivalents of calciumhydroxide relative to the fatty acid content, said fatty acid contentconsisting essentially of: (a) from about 40 to about 95% percent byweight of unsaturated C:16-C:22 fatty acids; (b) from about 5 to about60% by weight of saturated C:14-C:22 fatty acids; and (c) no more thanabout 6% by weight of moisture, insolubles and unsaponifiables; with nomore than about 20% by weight being in the form of glycerides; whereinfrom about 40 to about 65% by weight of the total product weightconsists of trans-C18:1 and C18:2 fatty acids; provided that when lessthan 0.75 equivalents of calcium hydroxide is present, said fatty acidcontent is at least 25% by weight saturated fatty acids.
 2. The fattyacid calcium salt of claim 1, wherein the ratio of trans-C18:1 and C18:2fatty acids is between about 60 and about 80% by weight of trans-C18:1fatty acids to between about 20 and about 40% by weight of C18:2 fattyacids.
 3. The fatty acid calcium salt of claim 2, wherein the ratio oftrans-C18:1 and C18:2 fatty acids is between about 65 and about 75% byweight of trans-C18:1 fatty acids to between about 25 and about 35% byweight of C18:2 fatty acids.